Cannot use form extensions

[NiKo2b]

Hello
I have followed all the installation guide, but I have a problem using form extensions. I tried with form_actions and bootstrap_collection but I have errors like :

Could not load type "bootstrap_collection"

Is there something else to add ? I'm using Symfony 3.1

[althaus]

You have to use the FQDN since Symfony 3:

use Braincrafted\Bundle\BootstrapBundle\Form\Type\FormActionsType;

class FooType extends AbstractType
{
    public function buildForm(FormBuilderInterface $builder, array $options)
    {
        $builder->add('actions', FormActionsType::class);
    }
}